The present invention relates generally to wrenches and, in particular, to a deformable wrench for an antenna assembly.
There are many situations where systems, mechanisms, or devices are assembled at a point of delivery where it is disadvantageous to attach a nut to a bolt or stud with too much or too little torque. Torque wrenches, however, are expensive and at times cumbersome to use. In addition, setting the torque wrench requires following detailed instructions, often difficult when installing systems, mechanisms or devices at the point of delivery.
An example of such a mechanism to be assembled at the point of delivery is an automotive vehicle antenna assembly. A typical antenna assembly includes a coaxial cable attached to a central conductor having a threaded stud formed on an end extending from a surface of the vehicle. An antenna mast is typically attached to the central conductor by an antenna mast nut. The mast extends for a given distance beyond the surface of the vehicle and although it is flexible, it is prone to breakage if bent with enough force. A greater danger for bending the antenna exists during delivery of the vehicle, whether on rail or truck, because of the tight vertical space restrictions for these carriers. Because of this danger, radio antennas are typically installed at the point of delivery, often an automotive dealership. In order to function properly, the antenna mast must be attached with the correct amount of torque. If the antenna is assembled with too much torque, the coaxial connections can be stripped, rendering the antenna inoperable. In addition, too much torque can chip the paint on the antenna mast nut. As a result, care is taken to not chip the paint on the mast nut, often resulting in an undesirable low amount of torque on the antenna mast nut. If the antenna is assembled without enough torque, the threaded stud may bend during normal vehicle operation or during automatic car washes, and eventually break. In addition, too little torque may result in poor electrical connection and lost reception.
It is desirable to provide a portable and inexpensive means for applying the proper amount of torque for attaching a fastener. It is desirable to provide a means for applying the proper amount of torque that does not chip or damage the coating of the fastener. It is desirable to provide a means for applying torque that will not over-torque the fastener. It is desirable to provide a reusable means for applying torque to a fastener.
It is an object of the invention, therefore, to provide a wrench that applies a proper amount of torque to a fastener without damaging the fastener or any coating on the fastener and that will not provide an excessive torque to the fastener. It is also an object of the invention to provide a wrench that is reusable.
It is another object of the invention to provide an antenna assembly that includes a wrench for applying the proper amount of torque to a fastener that may be advantageously reused.
The present invention solves the problems of the prior art and accomplishes the objectives noted above by providing a novel deformable wrench. The wrench is shaped generally like a wing nut and includes wing portions extending outwardly from a center portion. A socket aperture extends through a top and a bottom surface of the center portion and receives a fastening means. The fastening means may include, but is not limited to, a nut or the head of a bolt. Preferably, the walls of the socket aperture are of a smooth bore type. Alternatively, the walls of the socket aperture include an inwardly extending lip formed at an upper portion of the aperture. Preferably, the socket is hexagonal in shape. Alternatively, the socket may be shaped to fit various fastener profiles. The wrench is preferably sized to be manipulated by hand. The wrench is preferably constructed of an elastic material, such as, but not limited to, polypropylene. Importantly, the properties of the elastic material are such that the flex modulus of the wrench material cooperates with the geometry of the socket aperture to allow the socket aperture walls to deform elastically once a certain torque value has been reached. When elastically deformed, the walls of the socket aperture flex outwardly and xe2x80x9cstripxe2x80x9d past the points of the fastener, advantageously not allowing the wrench to apply more torque to the fastener. The wrench, after elastically deforming, advantageously assumes its original form and shape because of the properties of the elastic material of the wrench. The elastic material may be supplied from recycled material.
The present invention may be advantageously applied to any type of fastener where it is desirable to apply a torque amount without damaging the fastener or the fastener coating and without applying a torque amount greater than that is required. Because the socket aperture of the present invention extends through the upper and lower surfaces of the wrench, the wrench may also advantageously be used to apply a torque to fastening means attached to elongated studs or bolts. Alternatively, the wrench may be applied to a fastening means having a flange formed thereon for cooperating with the alternative inwardly extending lip of the socket aperture.
Furthermore, the wrench of the present invention may be made part of an automotive antenna assembly. The assembly includes an elongated antenna mast having a mast nut on one end. The antenna mast nut is preferably formed from hexagonally shaped stock. An end of the antenna mast nut is machined to form a rounded flange. The portion of the antenna mast nut directly abutting the flange includes a machined groove having a smaller diameter than the flange. The wrench receives the hexagonal antenna mast nut in the socket aperture. The lip on the walls of the socket aperture cooperates with the rim flange and groove to form a snap-fit connection that serves to retain the wrench in place on the mast nut and align the wrench with the hexagonal surface of the mast nut. The wrench is then used for applying a torque to the mast nut during installation of the antenna mast and assembly, while advantageously not chipping the paint coating of the mast nut. After use, the wrench may then be removed from the mast nut and placed in the automobile for possible future reuse.
The present invention may be constructed with various values of flex modulus to cooperate with various shapes and profiles of the socket aperture. The wrench is not limited to a generally wing-nut shape, but may also be shaped in various ways that are ergonomically suitable for hand-tightening of fasteners.
The present invention is particularly adaptable to build-at-home assembly kits having multiple fasteners where torque values are critical but where traditional torque wrenches are too expensive, too bulky, or too heavy to be made part of the assembly kit. The present invention may be advantageously placed in the packaging material. The present invention is more adaptable to smaller torque values that may be applied by a person using one hand, but the wing sections could be extended to provide additional torque, with a corresponding increase in the flex modulus properties of the elastic material.